how do investigators find “what caused the fire?” Or “what caused the shuttle to explode?” Or any root cause of some event where much or all of the evidence has seemingly been destroyed?

Question

how do investigators find “what caused the fire?” Or “what caused the shuttle to explode?” Or any root cause of some event where much or all of the evidence has seemingly been destroyed?

In: Other

Answer 1

Fire:

I trust you understand that fire needs a mixture…an optimum mix of fuel and air (plus heat).

When a fire FIRST begins, that mixture is OK but not perfect. This tends to leave fuel rich smoke and the fuel rich smoke leaves stains near that point. This is one way to tell where the fire began and by look at what is there you might find WHY the fire began. Analyzing the stains left by the smoke can tell you what exactly burned (gasoline and wood? or just wood?) which has implications.

Fun Fact: This rich smoke that comes out initially is the cause for “flash over.” The smoke that is from the beginning of the fire is rich in fuel. When the heat from the fire progresses and heats this rich smoke (assuming there is also O2) the smoke suddenly and forcefully ignites.